HEF4541BT,653

Programmable Timers And Oscillators Overview

The HEF4541BT,653 is a programmable timer from the Nexperia HEF4541B series. It integrates a 16-stage binary counter, an RC oscillator, and output control logic. The device operates on a supply voltage (VDD) of 3 V to 15 V. External components RTC and CTC set the oscillator frequency between 1 Hz and 100 kHz. An external clock at input RS can replace the internal oscillator. The counter divides the frequency by 2^8, 2^10, 2^13, or 2^16 based on address inputs A0 and A1. It features automatic power-on reset and low quiescent power dissipation.

Programmable Timers And Oscillators Feature Summary

• CMOS technology with wide supply voltage range from 3.0 V to 15.0 V
• Integrated 16-stage binary counter with selectable division ratios
• ESD protection: HBM exceeds 2000 V, CDM exceeds 1000 V
• Specified for ambient temperatures from -40 °C to +125 °C

Programmable Timers And Oscillators Applications

• Programmable timing circuits
• Frequency dividers
• Clock generation using external RC components

Programmable Timers And Oscillators Procurement Notes

Verify the ordering suffix ',653' against the manufacturer's current documentation to confirm the specific tape-and-reel packaging configuration. Confirm that the component meets the required temperature range specifications (-40 °C to +125 °C) for the intended application environment before finalizing procurement.

Programmable Timers And Oscillators Selection Notes

Select this component when a CMOS programmable timer with a 3 V to 15 V operating range is required. Ensure the design accommodates the SO14 package (SOT108-1). Verify that the external timing components (RTC and CTC) fall within the recommended ranges to maintain accurate oscillation frequencies between 1 Hz and 100 kHz.

Programmable Timers And Oscillators Part Context

The HEF4541BT,653 belongs to the HEF4541B family of programmable timers manufactured by Nexperia. This family utilizes standard CMOS logic processes. The 'BT' designation indicates the SO14 plastic small outline package variant, while the ',653' suffix typically denotes the reel packaging format.

Programmable Timers And Oscillators Replacement Considerations

Direct replacements must match the HEF4541B functionality and SO14 pinout. Other manufacturers producing compatible 16-stage programmable timers in SO14 packages may be considered if they meet the 3 V to 15 V supply and -40 °C to +125 °C temperature requirements.

Programmable Timers And Oscillators FAQ

How is the oscillator frequency determined?

The oscillator frequency is determined by external resistor (RTC) and capacitor (CTC) components connected to pins 1 and 2. The frequency range is typically 1 Hz to 100 kHz.

What are the available frequency division ratios?

The 16-stage counter divides the oscillator frequency by 2^8, 2^10, 2^13, or 2^16. These ratios are selected via the state of the address inputs A0 and A1.

How does the master reset function operate?

A HIGH level on the master reset input (MR, Pin 6) resets the counter independent of all other inputs. Resetting also disables the oscillator to minimize power dissipation.